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Algodonite

Algodonite
Algodonit - Houghton County, Michigan, USA.jpg
Algodonite - Houghton County, Michigan, USA
General
Category Sulfide mineral
Formula
(repeating unit)
Cu6As
Strunz classification 2.AA.10a
Crystal system Hexagonal
Crystal class Dihexagonal dipyramidal (6/mmm)
H-M symbol: (6/m 2/m 2/m)
Space group P63/mmc
Unit cell a = 2.6, c = 4.228 [Å]; Z = 2
Identification
Formula mass 456.2 g/mol
Color Gray, silver white, steel gray, tarnishes dull bronze
Crystal habit Massive, granular. Common texture observed in granite and other igneous rock
Fracture Sub-conchoidal
Mohs scale hardness 4
Luster Metallic
Diaphaneity Opaque
Specific gravity 8.38 (measured), 8.72 (calculated)
Other characteristics Non-magnetic, non-fluorescent
References

Algodonite is a copper arsenide mineral with formula: Cu6As. It is a gray white metallic mineral crystallizing in the hexagonal system. It has a Mohs hardness of 4 and a specific gravity of 8.38 - 8.72.

It was first described in 1857 from the Algodones silver mine, Coquimbo, Chile.


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Wikipedia

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